Machine for the preparation of pattern carriers for circular knitting machines

ABSTRACT

A machine for breaking off peripheral teeth from pattern discs used on knitting machines. The machine has a mandrel for holding the discs. The mandrel is operated from a first control means comprising both a gear box arrangement including gear and camming mechanism for imparting intermittent relative longitudinal movement between the mandrel and teeth breaking-off tools, and also an electrically controlled incremental drive means for intermittently rotating the mandrel from one tooth position to the next. A second control means in the form of a tape controls, inter alia, the selection of the breaking-off tools. The first and second control means are caused at the dictates of a third control means to function strictly in unison with one another.

United States Patent 1 Gell et al.

[ June 12, 1973 [54] MACHINE FOR THE PREPARATION OF PATTERN CARRIERS FOR CIRCULAR KNITTING MACHINES [75] Inventors: Dennis Gell, Leicester; Jan Hogbart Hvidsten, Ashby de la Zouch, both of England [73] Assignee: Stibbe-Monk Developments Limited, Leicester, England 22 Filed: Feb. 22, 1972 [21] Appl. No.: 228,030

[52] US. Cl. 225/97, 83/71, 83/219,

[51] Int. Cl B26f 3/00 [58] Field of Search 225/97, 103, 93;

[56] References Cited UNITED STATES PATENTS 2,990,702 7/1961 Schmidt 83/267 X Sheppard et a1 275/97 Knorr et a1. 225/97 57 ABSTRACT A machine for breaking off peripheral teeth from pattern discs used on knitting machines. The machine has a mandrel for holding the discs. The mandrel is operated from a first control means comprising both a gear box arrangement including gear and camming mechanism for imparting intermittent relative longitudinal movement between the mandrel and teeth breaking-off tools, and also an electrically controlled incremental drive means for intermittently rotating the mandrel from one tooth position to the next. A second control means in the form of a tape controls, inter alia, the selection of the breaking-off tools. The first and second control means are caused at the dictates of a third control means to function strictly in unison with one another.

20 Claims, 11 Drawing Figures Pafented June 12, 1973 10 Sheets-Shoat I Patented June 12, 1973 r 3,738,553

10 Sheets-Sheet 5 Patented June 12, 1913 3,738,553

10 Sheets-Sheet 6 Patented June 12, 1973 10 Sheets-Shut 7 QNN 0m w nw v6 3 mm nNN MNN vm v hm R m m 8 MB a E mm a Patented June 12, 1 973 10 Shoata-8hoot r:

Patented June 12, 1973 3,738,553

10 Shoots-Shoot 9 Patented June 12, 1973 10 Shoots-Shoot 10 MACHINE FOR THE PREPARATION OF PATTERN CARRIERS FOR CIRCULAR KNITTING MACHINES This invention relates to the preparation of'pattern information, particularly for producing patterns on knitted fabric on circular weft knitting machines, and is more especially concerned with apparatus for the selected breaking of bits from pattern discs on such machines.

Circular knitting machines using such pattern discs with frangible butts are well known and need not be described here. It is, however, necessary to mention that it is also known to provide at each feed of such a machine a stack of discs consisting of as many as 36 superimposed discs. Circular knitting machines having as many as 36 or even 48 feeds are now common, and machines with even more feeds and possibly more discs per stack are envisaged for the future.

Each disc is furnished, around its periphery, with a number of frangible teeth, usually 72, but discs with more or less teeth, are also available for use. Selected ones of these frangible teeth are broken off depending on patterning requirements.

Means for breaking off these teeth as required are known, one such machine for the purpose consisting of a manually operated key-board type instrument. A number of discs are loaded onto a mandrel which is in turn fitted into the machine which has a horizontal set of breakers (one per disc). The breakers required to be operative are manually selected by the operator after reading a squared off and coded plot of the required pattern. The mandrel with its discs are then moved sideways by a manual operation to break-off a tooth from pre-selected discs. The mandrel is then rotated to the next tooth position and the selecting and breaking procedure is repeated, and so on.

For a knitting machine having 36 feeds with 36 discs in a stack at each feed it will be readily appreciated that 72 operations as just described on each of the stacks at each feed, when performed manually, is a very lengthy and taxing business. It is also accepted that this method whereby the operator reads the information and manually selects the breakers gives a fault level of about 5 percent which faults only become apparent after a suitable length of knitted fabric has been produced. These faults thereupon have to be corrected by first determining the faulty discs and then making new ones by use of a hand-operated instrument similar to a pair of pliers.

This particular machine and others are described in a book entitled Jacquard Design & Knitting by J.B.Lancashire in Chapter headed Pattern Preparation Equipment."

Another machine described in this book is a semiautomatic one whereby a paper control tape is manually produced by a punched keyboard operator from a coded plot of the required pattern. This tape is then used to control a breaking machine in which a maximum of eight discs can be programmed at a time.

The last mentioned method of disc preparation is no more reliable and efficient than other known methods inasmuch that the discs which are programmed from a manually produced tape will inevitably contain a proportion of faults. The ability to programme only a limited number of discs, say eight at any one time is also a disadvantage when it is considered that some knitting machines already have as many as one thousand twelve hundred and ninety six discs and future machines may have even more.

It is accordingly one object of the present invention to speed up the preparation of pattern discs by preparing more discs at one operation than has heretofore been possible on known disc preparation machines, a particular aim being to combine this advantage with the use of a control tape produced by automatic means.

The production of such a control tape is described in a co-pending United Kingdom patent application Ser. No. 54785/69 filed by Stibbe Machinery Limited which application described the production of a squared-off plot from a colored original pattern. In this patent application, moreover, is described a means of editing the squared-off plot to comply with the designers wishes and then of producing a suitably punched control tape from this information. The tape can thereupon be checked on this apparatus as it can be used to produce a squared-off plot which can be visually checked to detect any faults in the tape before preparation of the pattern discs.

A further disadvantage of known disc teeth-breaking machines is their limited range in that one teethbreaking machine can only accommodate one size of disc. Also if discs of different gauge (i.e. different numbers of peripheral teeth) are to be programmed on one and the same machine different gear connections have to be made which necessitates replacing one pair of gears with another. These disadvantages can occur due to the range of disc patterning knitting machines produced by even one manufacturer. There are, however, several manufacturers of disc patterning knitting ma chines, each manufacturer having his own range of disc teeth-breaking machines. This system becomes very expensive in capital layout and idle time for teethbreaking machines where more than one type of knitted machine with disc patterning is employed in one factory.

It is accordingly another object of this invention to obviate the above disadvantages by the provision of an improved teeth-breaking machine capable of accommodating any size and gauge of disc at present known or likely to be employed in the future, the change to a different size or gauge of disc in such improved machine simply requiring the setting to appropriate positions of certain controls without any parts requiring to be changed. The aim in this regard is to enable a single teeth-breaking machine, set up in a factory employing several different types of disc patterning knitting machines to programme all the discs for all such different machines, thereby utilizing the single teeth-breaking machine to its fullest extent.

The machine of this invention for breaking off the peripheral teeth of pattern discs used on circular jacquard knitting machines is broadly of the known kind which not only includes selectable breaking-off tools and a mandrel on which are held fast in spaced apart relationship the pattern discs to be operated on at any one time, but is also automatically operable for the duration of the complete preparation of the set of pattern discs on the mandrel under control means. The improved machine is characterized in that the mandrel is primarily operated from a first control means comprising both a gear box arrangement including gear and camming mechanism for imparting intermittent relative longitudinal movement between the mandrel and the teeth breaking-off tools and also an electrically controlled incremental drive means for intermittently rotating the mandrel from one tooth position to the next, and in that a second control means is provided for, inter alia, controlling the selection ofthe said breaking-off tools, the two control means being caused, at the dictates of a third control means, to function strictly in unison with one another.

The improved teeth-breaking machine Of this invention also includes the provision of means for adjusting the relationship of the mandrel relative to the effective and operational position of the breaking-off tools, or vice versa, suchwise as to accommodate sets of discs of respectively different diameters. One form of such means may advantageously consist of a mandrel locating wheel with differently offset locating recesses each of which can be brought into operatlon, to receive an appropriate part of the mandrel assembly, dependent upon the diameter of discs to be programmed. An alternative form of said means comprises a carriage for cating the mandrel and cam means for moving this carriage to one of a multiplicity of locations. A still further alternative means for this purpose may consist of the provision of differently sized cams for operating the breaking-off tools, which cams can be brought into operation, one at a time, dependent upon the diameter of the discs to be programmed.

The aforesaid second mentioned control means may conveniently consist of a tape, e.g. of the punched type described in the hereinbefore mentioned co-pending United Kingdom application Ser. No. 54785/69, which tape not only bears the information for controlling the selection of the breaking-off tools but also information for controlling the starting and stopping of the gear box arrangement and indexing information for instructing the electrically controlled incremental drive means by which the mandrel is intermittently rotated.

The third mentioned control means may advantageously consist of electrical switches arranged to control the starting and stopping of the control tape once the programming of a set of discs has been started, said switches being triggered from at least one switching device rotating in timed relationship with the gear box arrangement.

In order that the invention may be more clearly understood and readily carried into practical effect, specific constructional forms of the improved teethbreaking machine will now be described in detail with specific reference to the following drawings, in which FIG. 1 is a cross-sectional view through one form of the teeth-breaking machine on line I I of FIG. 2,

FIG. 2 is a front view, partly in section, of the same teeth-breaking machine,

FIG. 3 is a part sectional view in the direction of arrow III in FIG. 2,

FIG. 4 is a partial end view as seen in the direction of arrow IV in FIG. 5,

FIG. 5 is a front view, partly in section, of the gear box arrangement,

FIGS. 6A and 6B together constitute an electrical diagram of the solenoid selector circuitry,

FIG. 7 is a cross-sectional view similar to FIG. 1 showing an alternative form of the improved teethbreaking machine,

FIG. 8 is a detail plan view of part of this alternative arrangement, as seen in the direction of the arrow VIII in FIG. 7 and showing, more particularly the mechanism for sliding the breaker cams,

FIG. 9 is a part-sectional front view, similar to FIG. 2, illustrating the mechanism included in the alternative form of the machine for moving the breakers sideways, and

FIG. 10 is a block diagram of an electronic function unit in the nature of a gear box embodied in the machine.

THE MANDREL In FIGS. 1 and 2 is shown the mandrel assembly MA in relation to the breaker unit BU which assembly in this specific arrangement comprises a complete set of twenty four discs 1 taken from a pattern unit provided at one selection station of a circular knitting machine. Although this particular arrangement is not essential, it is preferred as the discs can, after programming, all be assembled onto the same pattern unit center for subsequent fitting onto the knitting machine, The reference numeral 5 designates a locking collar, arranged to bear on the relevant end of the mandrel. The mandrel assembly MA in this first example may comprise odd and even discs alternately positioned in a case where the pattern width of the knitting machine dictates the necessity for half gauging.

The left hand end of the mandrel 2 is surrounded by a collar 6 which is fixed thereto by a pin 7. This collar has attached to its outer end a key 8 for coupling the mandrel assembly MA to the gear box GB shown in FIG. 5. The right hand end of the mandrel assembly MA as seen in FIG. 2 consists of a manually operable locking means 9 which has the locking collar 5 attached to it by a pin 10. The center of the locking means 9 is constituted by a threaded portion 9a of a stem which fits into an axially extending tapped hole 2a in the mandrel 2.

MANDREL LOCATION R.I-I.

The mandrel assembly MA is located at its right hand end, as shown in FIG. 3, by the hand locking means 9 which rests on a ledge 26a of a housing 26. The horizontal location of the mandrel assembly is governed by a wheel 12 which has therein several precision cut recesses 12a which are offset to respectively different extents from radial lines so that different horizontal locations of the mandrel assembly are possible dependent upon the diameter of the discs 1 to be programmed. The wheel 12 is manually rotatable about a center screw 13 which is fixed into the housing 26. A stop pin 14 in the housing 26 is locatedin one of a circular series of holes 12b in the wheel 12 dependent upon which recess 12a in the said wheel is required for locating the mandrel. As shown in FIG. 2, the stop pin 14 is biassed into the relevant hole 12b by means of a spring 15, and is held out clear of the wheel 12 to enable the latter to be turned by means of a knurled head 140. In order to register which diameter of disc is being programmed, a switch 16 is provided for each cut-out recess 12a. The switches 16 are reed switches housed in a block 17 and each is closed only when the relevant one of a number of permanent magnets 18 in the wheel 12 is in line with it. Each magnet 18 is located at an appropriate radial position to operate only one reed switch 16.

For holding the mandrel assembly MA firmly in its desired location there is provided a gate 28 which is pivotable about a shoulder screw 29 to allow access to the said assembly. The fitting of gate 28 into the slot 26b (see FIG. 3) pushes down a plunger 33 against the action of a spring 34 to close a micro-switch 35.

MANDREL LOCATION L.H.

At the right hand side of FIG. 5 is shown the left hand end of the mandrel 2 and the surrounding collar 6 with its key 8. The mandrel 2 projects into a hole 19a in shaft 19 and the key 8 locates in a mating keyway 19a in the end of this shaft. A locking ring 20 is turned clockwise, as seen in FIG. 4, to hold the mandrel assembly MA. But to facilitate mating of the key 8 in the keyway 19a the locking ring 20 has cut therein a recess 20a. The locking ring 20 is fixed to a ring 21 which locates on a flange 1912 on the shaft 19. 4

Moreover, the shaft 19 has an annular flange 190 which is enclosed in a braking system to prevent the said shaft and the mandrel 2 from rotating more than the precisely required degree. Two collars 22 are pressed onto opposite sides of the flange 190 by means of spring washers 23 held in position by pins 24. The male and female parts 25 and of the brake unit are threaded together and the amount of tightening imparted to the male part 25 is dependent upon the amount of braking action required. The brake unit is prevented from rotating together with the shaft 19 by a pin 31 located in a carriage 32 (FIGS 4 and 5). The shaft 19 is rotationally supported at one end in the carriage 32 and its other end carries a co-axial gear 150. In addition, the portion 19d of the shaft 19 is reduced in diameter to provide an annular flange 19e which is freely held in a horizontal slideway 151a on the end of' a shaft 151 which does not rotate and the operation and function of which will be hereinafter described. The gear 150 is driven from the gear box GB by a pinion 152 on a shaft 153.

Referring now to FIG. 4 it will be seen that the carriage 32 is slidingly located on a support 156 through the medium of T-plates 157 located in a slideway 156a. This is to facilitate the movement of the mandrel assembly MA in a horizontal relationship with respect to the hereinbefore described wheel 12. Also rotationally supported in the carriage 32 is a shaft 158 which has attached to one end thereofa collar 139 into which can be inserted a tommy bar 160 for turning the shaft 158.

Turning of the shaft 158 causes a barrel cam 161 to turn through the medium of a key 162. Located in a cam track 161a in the said barrel cam is a follower 163 which is fixed in the support 156. Accordingly, and because the follower 163 is stationary, turning of the shaft 158, to which the barrel cam 161 is fixed, causes this cam to move axially and either push on a locking nut 164 or a sleeve 165 to move the entire carriage 32 and associated parts. The plunger 166 and spring 167 simply serve to locate in a dimple in the side of the barrel cam 161 as each of the different positions are reached. The said plunger therefore suitably re-locates the mandrel assemble MA for different diameter discs, the drive from the pinion 162 to the gear 150 being unaffected as the variation is so small as not to diminish the drive efficiency. Attached to the end of the shaft 158 is a switch-actuating blade 168 which closes one of a number of switches 169 dependent upon the position of the mandrel assembly MA and the diameter of the discs concerned.

THE BREAKER UNIT The mechanism of the breaker unit BU depicted in FIGS. 1 and 2, is housed within the side plates 11 and 27 which are held apart in the correct location by a base plate 36, bars 37 and 38 and various shaft arrangements as will become clear in the following further description.

One of a row of breakers 39 is shown in FIG. 1 in a retracted position and housed in horizontal sliding relationship with the breaker bar 37 which is cut with a series of slots 37a to house said breakers 39. The breakers 39 are held in correct relationship by a cover bar 40 which is fixed to bar 37 by screws 41. Each of the series of breakers 39 is furnished with a breaker nose 39a at its front end and a projection 3912 at its lower rear end.

Also as shown in FIG. 1, all of the projections 3912 are hooked over a lip 42a at one end of a pulling bar 42 which is fixed at its other end to a housing 43 by means of screws 44. Housing 43 is in turn fixed to a bracket 45 by screws 46 which bracket. is centrally located within the end plates 11 and 27 and is fixed to a slider 47 by means of screws 48. Slider 47 is slidable from front to back of the breaker unit BU in a slideway 36a provided in the base plate 36. A roller 49 secured on a pivot pin 50 within a slot 45a in the back of the bracket 45 co-acts with a cam 51 secured to a shaft 52 driven from the gear box GB as will be hereinafter described. The movement of this sliding assembly is against the action of a spring 53 which is coiled around a rod 54 screwed into the back of the breaker bar 37.

Housed within slots 43a within the housing 43 in a vertical sliding relationship is a row of interruptors 55 which are held in position by a bar 56 attached to housing 43 by screws 57. A cut-out 55a formed in the upper rear portion of each of the interruptors 55 enclosed the free end of an arm 58a of a pivoted lever 58. There is a row of the pivoted levers 58 spaced apart by thrust washers 59 all of which are located on a rod 60 and are held between end brackets 61 and 62 also arranged to pivot on rod 60 located within the said plates 11 and 27 (see FIG. 2).

Attached to the brackets 61 and 62, by shoulder screws 63 and 64, are rollers 65 and 66 which operate, in contact with cams 67 and 68 and against the influence of springs 70, to turn the end brackets 61 and 62 and associated mechanism about the rod 60. Cams 67 and 68 are rigidly secured upon a shaft 69 which locates within the side plates 11 and 27 and is driven from the gear box GB in a manner presently to be described. A bar 70 is fixedly located between the two end brackets 61 and 62 by dowel pins such as 71.

Each of the pivoted levers 58 also has a further and rearwardly directed arm 58b the free end of which is held within a cut-out 72a in the front edge of a corresponding selector 72. The selectors 72 are held in vertical sliding relationship in slots cut in a selector housing 73 (FIG. 1) which is fixed to the side plates 11 and 27. The bar 38 serves to maintain these selectors properly aligned and also houses springs 74 within holes 38a.

. The springs 74 co-act with projections 72b on the selecof the selectors 72 shown in FIG. 2 have cut-outs in their rear edges at heights corresponding to the other two levels of solenoid armatures 76 shown in FIGS, 1 and 2. The solenoids 77 are located, as can be seen in FIG. 1, by the armatures 76 within holes 73a in the selector housing 73. These armatures 76 are retracted against the action of springs 80 upon energization of the solenoids 77 but always remain within the holes 73a. That is to say, the said armatures are only retracted sufficiently to be clear of the corresponding selectors 72.

The solenoids 77 are fixed to straps 81 by lock nuts 82. These straps are in turn fixed to bars 83 and 84 by means of screws such as 85 and 86. The bars 83 and 84 are themselves fixed to end plates such as 87 located at opposite sides of the unit in line with the side plates 11 and 27. The armatures 76 extend through the solenoids 77, and have rearwardly projecting ends of reduced diameter on which are fixed buttons 88.

Two spaced apart levers, one of which is indicated at 89 in FIG. 1, are fixedly held in the same relationship to shaft 90 by dowel pins such as 91. Extending across the upper ends of these levers 89 is a plate 92 which is fixed in position by screws 93 and is adapted for cooperation with the buttons 88 of the solenoid armatures 76. Another lever 94 is also fixedly held to the shaft 90 by means of a dowel pin 95. The lever 94 has, located on a spindle 97 within a slot 94a formed in its free end, a roller 96 for co-operation with a cam 98 fixed upon the shaft 52. The movements of levers 89 and 94 caused by the cam 98 are against the action of a helical spring 99 surrounding a plunger 100. There are, in fact, two such springs and plunger arrangements, one in each end plate 87, for action upon respectively opposite ends of the plate 92.

There are in this particular example 24 solenoids 77, 24 pivoted levers 58, 24 interruptors 55, 24 breakers 39 and 24 selectors 72, i.e. three groups each of eight such selectors, the selectors of each group having therein rear cut-outs at the same level.

THE GEAR BOX The gear box GB shown in FIG. is not a true dimensional detail drawing, the gear box having been laid out flat so that each component can be easily seen. It is accordingly first necessary to point out that a shaft 170 is coupled to and drives the shaft 58 of the breaker unit BU; a shaft 171 is coupled to and drives the shaft 69 of the breaker unit; the shaft 153, through the medium of intermeshed gears 152 and 150, drives the mandrel assembly MA rotationally and the shaft 151 drives the said mandrel assembly longitudinally.

The main drive is from an electrical motor, e.g. a 1% hp. Holroyd Verso, and a gear box (not shown) which are connected to a pulley belt 172 arranged to drive a shaft 173, via a pulley 174. The shaft 173 is the input to a clutch and brake unit 175 which is electrically controlled, in a manner presently to be described, to give accurate control over the breaker unit BU. The output from the clutch and brake unit 175 is via a shaft 176 journalled in a side wall 177 of the gear box GB to a spur pinion 178 which drives a spur gear 179. This gear is on a shaft 180 which is journalled in the side walls 177 and 181.

A gear 182 fixed to the shaft 180 drives a gear 183 on the shaft 171 to control the movement of breaker selection plates. Moreover, the gear 182 also drives an idler gear 184 which in turn drives a gear 185 on the shaft to control the movement of the breakers and solenoid cancel movement.

A barrel cam 186 secured upon the shaft has therein a cam track 186a designed to control the movement of a block 187 by operating on a roller cam 188 in said block. The shaft 151 on which the block 187 is locked is prevented from rotating by a roller cam 189 which is fixed to a mounting 190 attached to the base 191 of the gear box GB. The shaft 151 is located in needle bearings 192 and 193, located in housings 194 and 195 mounted respectively in and on the side walls 177 and 181. The block 187 is fixedly located by a key 196 and also by a locking nut 197 which holds it against face ll5lb of the shaft 151.

As previously described, the end of the shaft 151 has a horizontal slideway 151a in which the flange 19e of the shaft 19 is free to rotate, the walls of this slideway serving to push or pull the shaft 19 and hence also the mandrel assembly MA for the butt breaking operation.

The mandrel rotation, also as previously described, is effected through the shaft 19 from the gear 150 in turn driven from the gear 152 on the shaft 153. The latter is driven, via coupling 198, from an output shaft 199 which extends from the gear box 154 located in the side wall 177 of the main gear box GB. The drive to the gear box 154 is from an electrically controlled incremental driver which, in this example, is a Unimatic stepper motor 155 of a commercially available type having two hundred steps per revolution. The gear ratio from the stepper motor 155 to the mandrel assembly MA is 15 to 1 which means that every revolution of the mandrel takes three thousand steps of the stepper motor. For this reason it is necessary to know not only which revolution of the mandrel is taking place, but also which of the fifteen revolutions of the stepper motor is taking place during the mandrels one revolution at any given time.

For monitoring this information two Galium Arsnide switches 200 and 201 are provided (see FIG. 5). The switch 200 registers a revolution of the stepper motor 155 every time a blade 202 passes between its contacts. For this purpose the blade 202 is attached to the rotating shaft of the stepper motor 155 by means of screw 203. The switch 201 registers a revolution of the shaft 19 and hence also of the mandrel assembly MA every time a blade 204 passes between its contacts, the said blade for this purpose being attached to the gear 150. A Galium Arsnide switch is a commercially available product and works on the principle of transmitting an electrical signal from one face, in this case 200a or 201a, to a receiving face 200b or 20lb an interruption of this signal being caused by passage of the blade 202 or 204 between such faces.

The stepper motor 155, as stated earlier, requires two hundred steps to make one revolution. Each step is caused by a pulse of electricity, the number of pulses being governed by the controller from the control tape as will be hereinafter described.

In the particular example now being described the stepper motor 155 is used to rotate the mandrel. There are, however, other forms of electrically controlled incremented drives such, for instance, as a brake clutch system. The latter requires an electric motor driving a brake clutch and a multi-position switch on the output of a gear box driven from the said brake clutch, in which instance a feed back through a controller from the switch to the brake clutch can then determine the operating cycle of the brake and clutch. Such a system is not, however, so commercially viable as it would require much larger gear reductions and greater capital outlay.

VANE SWITCHES A vane switch assembly VSD is shown in FIGS. 2 and 3. Vanes, constituted by discs 128, 129 and 130 are attached to the end of the shaft 52, whilst switches 131, 132 and 133 are attached to the side plate 27 by means of a bracket 134. These switches are vane switch detectors as produced under the trade name Mullard and each of them operates as a contactless switch.

Each vane switch is identical to the switch 133 which, as shown in FIG. 2, consists of an oscillator coil 133a and a detector winding 133b, insertion of a metallic vane in the gap between these two stopping the electrical output from the vane switch. Accordingly, in this arrangement an electrical signal is passed whenever a gap, such as that designated 130a in the disc 130,

passes between an oscillator coil, such as 133a and adetactor winding such as 133b.

SOLENOID SELECTION In FIGS. 6A and 6B is illustrated a detail of the circuitry used for the energization of the solenoids from information received from the control tape, vane switches and electrical controller.

The information for selective solenoid energization is contained on four tracks of the control tape T read by readers TR1, TR2, TR3 and TR4 (see FIG. 6A). In this particular example twenty four bits of information are required to energize or not twenty four solenoids 77 (see FIG. ll): accordingly, there are six bits of information in a longitudinal row in the form of punched holes or no punched holes, on each of the four tracks of the control tape T.

The first row of information is read by readers TRl, TR2, TlR3 and TR4 and fed into a memory store S1 due to the timing pulse T1, the second row of information is fed into a memory store S2 due to the timing pulse T2, and so on, until all the stores S1 to S6 have received the appropriate bits of information. An output from each memory store for each bit of information is connected to an appropriate one of twenty four NAND gates A1 to A24 (see FIG 6B). The information from a memory store is in the form of a high level (1) or a low level in the case ofa hole in the tape, the information is to energize the solenoid 77 for the appropriate breaker to be made operative and is a high level (1).

The breaking tools are selected at the dictates of one of the vane switches, VS2, a high level input 1 being received at the NAND gates A1 to A24. Therefore an 0 output is emitted from the NAND gates receiving two I inputs, and a 1 output is emitted by those receiving an 0 input and a 1 input. The O outputs operate a transmitter driver circuit which energizes the appropriate solenoid 77. Each of the outputs from the NAND gates is, of course, connected through one such circuit arrangement to operate one solenoid.

Selection verification is obtained through microswitches M1 to M24 (FIG. 6A) arranged one over each selector 72. A micro-switch is closed when the corresponding selector 72 rises up under influence of its spring 74 after the relevant solenoid has been elected.

The closing of a micro-switch 235 (see FIG. 1) will cause an input 0 to be transmitted to each of the inverters D1 to D24 which is inverted to a 1 and fed into the appropriate comparator C1 to C6 (FIG. 6A). An open micro-switch will, of course, result in an 0 input being fed to the appropriate comparator.

This information is compared with information previously fed to comparators C1 to C6 from the memory stores S1 to S6. If all the information compared corresponds, the output from the comparator is a 1 fed to an inverter N1 or N2 (FIG. 6B) which, if all the inputs received are 1 level, is inverted to O and fed to the appropriate NAND gate B1 or B2. The NAND gates B1 and B2 are connected to the vane switch VS3 (top left-hand corner of FIG. 6A) and when a signal of the 1 level is sent to NAND gates B1 and B2 which have received an 0 input from the comparators, an 0 output is fed to the tool fault-registering circuit which will not light a warning light and stop the machine. If, however, a signal of the 0 level is received from any of the comparators C1 to C6, the inverter N1 or N2 will not invert it and a 1 level output will be fed to the appropriate NAND gate B1 or B2 causing a 1 output to the tool fault-registering circuit as a result of which the machine will be stopped and the warning light will-be lit.

STEPPER MOTOR INPUT In order to design a universal tooth-breaking machine capable of programming discs with different numbers of teeth it is first necessary to determine the common denominator into which all of these numbers of teeth, ranging from 48 to 96 will divide. This number corresponds to the number of pulses or steps of the stepping motor to each revolution of the mandrel; in the specific example now being described this number is 52,416. When programming a stack of half gauging discs each furnished with 72 teeth, it necessary to increment the mandrel assembly MA 144 steps per revolution. Accordingly, the number of pulses per breaking operation, or half tooth pitch, is equal to 52,416 divided by 144 which is 364 steps of the stepper motor to each increment of the mandrel. The stepper motor makes 200 steps/rev. which amounts to nearly two revolutions for each increment of the mandrel.

A gear reduction suited to perform such an operation would be a very large one having backlash problems. In accordance with the present invention these problems have been overcome by the use of a system including an electronic gear box as now to be explained with reference to FIG. 10 which, as previously mentioned, is a block diagram of the electronic function unit in the nature of an electronic gear box.

Referring to FIG. 10, it will be seen that a pulse generator 205 feeds pulses both to a counter 206 and also a latch 207. A memory 208 receives information from the tape corresponding to the figure 364 calculated as above and dependent upon the number of teeth on the disc and whether the latter are for half gauging or not. This information 364 is fed to a comparator 209 which continually compares it with the information from counter 206. When 364 pulses from the generator 205 have been received by comparator 209, a signal is sent to a latch 210 which causes the closing of a gate 21 1 and stops any further pulses passing through it. The latch 210 is initially caused to open the gate 211 by a push button control for system run, and during operation after being closed, as just described, by the vane switch VSl.

, Pulses (p, are generated by a pulse generator 212 at a much faster rate than 4),, and these are fed to a X125 multiplier 213 and also to a divider 214. Every time 125 pulses have been received by multiplier 213, latch 207 is re-set and closes gate 215. The pulses are also counted up in divider 214 which will count 125 before gate 215 is closed asjust described. The divider 214 has a clearance capacity set at 2184 and when this number of pulses is reached, a signal is sent to a switch 216 and its counter is re-set to zero and is instantaneously ready to count any remaining pulses over 2,184 in the last sequence of 125 which are held in the divider. In order for the pulses to pass through the gate 215 it is necessary for a pulse qb, to operate the latch 207 to open the gate 215 which action starts the sequence just described.

It will therefore be readily appreciated that 4), pulses are generated many times faster than (i), pulses and every time the divider 214 has counted 2,184 pulses a signal passes to the switch 216 and causes the stopper motor 155 to increment one step. This function is operated through the switches 216 which are cycled to their next step position by each pulse received from the divider 214 which causes a 12V current to the coils of the stepper motor 155 to be fed to the next coil in sequence as is standard practice for such motors.

Accordingly, for the initial 364 pulses which were called for from the tape T, a total of only 20 pulses (364 X l25)/2,l84 are eventually needed to move the mandrel on one pitch.

ALTERNATIVE ARRANGEMENT In the arrangement of the machine so far described different diameter discs are accommodated by moving the mandrel location, and the breaking of teeth is performed by shogging the mandrel assembly MAfIt is proposed in the alternative form of the mechanism to be described to have a fixed mandrel location and to move the breaking tools different amounts: also to shog the breaking tools to break off the teeth instead of shogging the mandrel assembly.

This alternative form of machine is illustrated in FIGS. 7, 8 and 9. As will be seen, the cam 51 on shaft 52 in the first described machine is replaced with a longer cam 220 having faces of different heights along its periphery. This cam 220 is slidingly held in fixed rotational relationship with shaft 52 by means of a key 221 and also has cut therein an annular track 220a. A roller 222 freely located in this track is attached to one end of a centrally pivoted lever 223. By moving this lever, the cam 220 can he slid along the shaft 52 to bring the desired cam face into cooperation with a roller 224 on a support S. The opposite end of the lever 223 is in the form ofa simple handle having associated therewith a number of micro-switches 225 and spring latches 226 corresponding to the number and the positions of the cam face heights on cam 220. The micro-switches 225 correspond to the reed switches 16 of the first described form of the machine.

In the alternative form of the machine, moreover, the breakers 39 are located on a sliding bed 227 arranged to slide longitudinally of a breaker bed 228. The interrupters, 229, in this second example are broader at their lower ends so as to remain in contact with the breakers 39 during a teeth-breaking operation.

To facilitate a description of the movement of the breakers 39 longitudinally, reference is made to FIG. 9 wherein is depicted a roller 230 mounted upon the relevant end of the sliding bed 227. A barrel cam 231 having therein a cam track 231a is fixed to a shaft 232 which is journalled in the side plate 11 and also carries a gear 233. The latter is arranged to be driven by a gear 234 fixed to the shaft 69. Thus, rotation of the shaft 69 causes the gear 234 to drive the gear 233 which in turn rotates the barrel cam 231. The cam track 231a in the said barrel cam is designed to shog the breakers once every revolution through the medium of the roller 230 mounted on the slide 227.

The principal parts of the breaker unit remain unchanged in the alternative form of the machine except for the use of a fixed positional mounting for the mandrel assembly MA. The longitudinal drive of the mandrel from the gear box GB shown in FIG. 5 is, of course, no longer necessary nor is the changeable mandrel location shown in FIGS. 4 and 5.

OPERATION CYCLE For the sake of convenience and efficiency several mandrel assemblies MA are employed so that as one with a set of discs thereon is being operated upon another can be prepared,i.e. have a new set of discs fitted, whereas the previously programmed assembly can be dismantled, i.e. have its programmed discs removed.

In this particular method of disc preparation it is convenient that each mandrel assembly shall have twenty four discs, made up of one stack of discs from one feed station of a knitting machine. There is, however, no limitation in this respect, as this method is merely one convenient way of loading and storing the information of a pattern original for a particular patterning arrangement on a particular knitting machine. The reading and storing of information for a pattern original can be performed and progarmmed within the scope of copending U.K. patent application Ser. No.54785/69 to suit other knitting machine patterning arrangements such, for instance, to programme one disc from each of 24 stacks or pattern units of a knitting machine.

1. Accordingly, the first operation is to load the new discs on to a mandrel such as 2 in preparation for loading the complete mandrel assembly MA on to the disc preparation, i.e. teeth-breaking, machine.

2. The mains isolator is switched to the ON position to start the motor running, and the mains ON button is also depressed to supply electrical power of the various inputs of the machine.

3. The location means for the mandrel assembly shown in FIGS. 3 and 4 are set to the relevant position depending upon the diameter of the discs being progarmmed.

4. The datum set" button is pressed so that the mandrel locking means shown in FIGS. 4 and 5 is rotated to the correct position for starting the mandrel in for the breaking operations. This position is governed by a reed switch 235 fixed to the sliding housing 32 by bracket 237 and switched by a permanent magnet 236 set in the collar 21.

5. The appropriate tape T is now loaded into the tape reader and run to its start position.

6. The complete mandrel assembly MA is thereupon loaded into the machine by sliding it to the left in FIGS. 2 and 5 so that the key 7 locates in the keyway 19a and the knurled locking collar 20 is turned to secure the as- 13 sembly. At the right hand end of the assembly, the gate 28 is swung to its locking position as shown in FIG. 3 and the micro-switch 35 is closed. The datum set" button is again pressed as in 4. above to ensure correct radial alignment of the mandrel assembly, non-correct alignment of which will show on the control panel as a datum set fault red light.

7. Next, the control tape T is restarted by pushing a cycle start switch (not shown). It is to be clearly understood, however, that the tape will not start again unless certain conditions prevail. Thus, for instance, the micro switches 35 must be closed. Also, the vane switch VSl must be so aligned that the gap in the vane allows an electrical output from the switch which verifies that the mechanically rotating parts of the gear box GB and the breaker unit BU are in the correct starting position. The tape will also instruct the memory latch 208 of the stepper motor increments and whether the steps are for a half gauge or full gauge arrangement.

8. Pressing the cycle start button will now engage the clutch and move the control tape from which the first set of breaking information is taken to the memory stores 81 to S6 as described previously after which the tape stops automatically under its own instruction.

9. The vane switch VSl will also open the latch 210 shown in FIG. to start the sequence of events previously described to increment the mandrel to its first breaking position.

10. The information from the memory stores S1 to S6 as explained with reference to FIG. 6, is now used under instruction from VS2 to energize the solenoids 77.

11. The mechanical selection movement now takes place: that is to say, the cam 67, no longer holding down the bank of pivoted levers 58, allows this assembly to rotate under the influence of the spring 70. In this way certain pivoted levers 58 rotate anti-clockwise, as viewed in FIG. 1, and some remain stationary. The levers that are to rotate are determined by which solenoids 77 are energized, i.e. energization of relevant solenoids causes their armatures 76 to withdraw from operative association with corresponding selectors 72, which latter consequently move upwards under influence of their springs 74. The selectors 72which move upwards correspond to the interrupters 55 which are moved downwards due to their association with the other arms of pivoted levers 58. The lower ends of selected interrupters therefore move into positions behind their respective breakers 39.

12. The selection of the breakers 39 having been made, the solenoids previously energized are now deenergizcd due to the continued rotation of VS2 which will only allow a signal to be transmitted, and hence the solenoids to be energized, whilst there is a gap in the vane 129.

13. The next in the sequence of automatic events is the verification of tool selection which is carried out as described with reference to FIG. 6 during thetime of transmission by VS3 due to a gap in the vane 130.

14. The stepper motor 155 having now finished incrementation of the mandrel, the selected teeth la are broken off from their discs 1. In this connection the cam 51 first rotates to push forward on the roller 49 which in turn pushes interrupter housing 43. As certain of the interrupters 53 in this housing are in engagement with their respective breakers 39 the noses 39a of the latter are as a matter of course pushed into interference with the teeth 1a of disc l as viewed in FIG. 1. Continued rotation of the drive causes the cam 186 to push sideways the roller 188 to shaft 151 of the gear box GB. As a consequence the mandrel assembly MA is caused to move sideways as viewed in FIG. 2. The result of this movement is to cause the respective breaker nose 39a to break the predetermined tooth off the relevant disc 1.

The cam 186 then also causes the mandrel to move back to its original position, when continued rotation of the drive will cause the operative part of the cam 51 to disengage from the roller 50 which, together with the bracket 45, the housing 43, the interruptors 55 and the pulling bar 42, functioning to pull the operative breakers 39, all move under the influence of the spring 53 to the inoperative position as shown in FIG. 1.

15. The operative face of cam 67 thereupon also comes into contact with the roller to turn all of the pivoted levers 58 to the position shown in FIG. 1 which movement lifts all the interruptors 55 and pulls down all the selectors 72. 7

l6. Thereafter,the solenoid armatures 76 are all returned to an engaged position with selectors 72, by means of the plate 92 under the influence of cam 98.

17. The last mentioned operation brings the mechanical systems of the gear box GB and breaker unit BU back to the start position, and under instruction from vane switch 131 the procedures 9 16 above being repeated. This occurs if the stacks of discs being programmed are set for half gauging as the information contained in stores S1 to S3 is used to energize alternate solenoids 77 as in procedures 9 16 above and the information from stores S4 to S6 is now used to energize the intermediate solenoids 77 and the procedures 9 l6 repeated. This requires that, as previously explained, for half-gauge arrangements, the mandrel will only index half a butt pitch.

18. The procedures 8 17 are now repeatedin the case of half-gauging arrangements until all the longitudinal rows of butts have been programmed on one mandrel.

If the programme were for normal or full gauge arrangements the information in stores S1 to S6 would be used simultaneously and the tape incremented to present new information every breaking cycle.

19. The mandrel assembly can now be removed from the breaker unit and replaced with another one requiring programming at which point procedures 6 18 are repeated.

We claim:

1. A machine for breaking off the peripheral teeth of pattern discs used on circular jacquard knitting machines comprising, in combination, a mandrel on which are held fast, in axially spaced apart relationship, pattern discs of a set to be operated on at any one time;

a corresponding set of teeth breaking-off tools which are selectively operable for action upon the teeth of predetermined ones of the said set of pattern discs; means for automatically operating the mandrel; means for automatically operating the breaking-off tools for the durationof the complete preparation of the set of pattern discs on said mandrel, and means for controlling both of said operating means: the said machine being characterized in that the mandrel is operated from a first control means comprising both a gear box arrangement including gear and camming mechanism for imparting intermittent relative longitudinal movement between the mandrel and the teeth breaking-off tools and also an electrically controlled incremental drive means for intermittently rotating the mandrel from one tooth position to the next, and in that a second control means is provided for, inter alia, controlling the selection of the said breaking-off tools, the aforesaid two control means being caused, at the dictates of a third control means to function strictly in unison with one another.

2. A toothed disc preparation machine according to claim 1, which also includes means for relatively adjusting the mandrel and the breaking-off tools to permit the machine to accommodate sets of discs of respectively different diameters.

3. A toothed disc preparation machine according to claim 2, wherein the said last mentioned means consist of a mandrel-locating wheel having therein a plurality of recesses which are laterally offset to respectively different extents from lines extending radially to the axis of the said wheel, the latter being turnable to present a selected one of the recesses, dependent on the diameter of the discs to be programmed, for reception ofan appropriate part of the mandrel assembly.

4. A toothed disc preparation machine according to claim 2, wherein the said last mentioned means comprise a carriage for locating the mandrel, and cam means for moving this'carriage to one of a multiplicity of locations relativelyto the breaking-off tools depending on the diameter of the discs to be programmed.

5. A toothed disc preparation machine according to claim 1, wherein there is a fixed mandrel location, and means are provided for moving the teeth breaking-off tools to different extents in relation to such location depending on the diameter of the discs to be programmed.

6. A toothed disc preparation machine according to claim 1, wherein the breaking-off tools are located on a sliding bed and cam means are provided for shogging the said bed and hence also the tools relatively to the mandrel for breaking-off disc teeth.

7. A toothed disc preparation machine according to claim 5, wherein the means for projecting the said tools into their teeth breaking positions include a group of differently sized cams which is adapted to be shifted to bring the individual cams into operation selectively, one at a time, to effect projection of the tools to respectively different extents radially with respect to the fixed mandrel depending on the diameter of the discs to be programmed.

8. A toothed disc preparation machine according to claim 1, wherein the said second control means consists of a tape which not only bears the information for controlling the selection of the breaking-off tools but also the information for controlling the starting and stopping of the gear box arrangement, and the indexing information for instructing the electrically controlled incremental drive means by which the mandrel is intermittently rotated.

9. A toothed disc preparation machine according to claim 1, wherein the electrically controlled incremental drive means for intermittently rotating the mandrel includes a stepper motor.

10. A toothed disc preparation machine according to claim 8, wherein the said third control means consist of electrical switches arranged to control the starting and stopping of the control tape once the programming of a set of discs has been started, said switches being adapted to be triggered from at least one rotary switching device rotating in timed relationship with the gear box arrangement.

11. A toothed disc preparation machine according to claim 10, wherein the electrical switches are contactless vane switches each comprising an oscillator coil and a detector winding, insertion of a metallic vane in a gap between which stops the electrical output.

12. A toothed disc preparation machine according to claim 8, wherein the tape serves, inter alia, toprogramme selective operation of a bank of solenoids of which there is one to each tooth breaking-off tool, the condition of the solenoids at any one time determining whether the corresponding tools are selected to their operative or inoperative positions.

13. A toothed disc preparation machine according to claim 8, wherein there is provided an electronic function unit incorporating both a pulse multiplier and a pulse divider wherein electrical pulses controlling the electrically controlled incremental drive means are a predetermined fraction of pulses emitted from a pulse generator at the instruction of the tape.

14. A machine for breaking off the peripheral teeth of pattern discs used on circular jacquard knitting machines comprising, in combination, a mandrel on which are held fast, in axially spaced apart relationship, pattern discs of a set to be operated on at any one time; a corresponding set of teeth breaking-of tools which are selectively operable for action upon the teeth of predetermined ones of the said set of pattern discs; means for automatically operating the mandrel; means for automatically operating the breaking-off tools for the duration of the complete preparation of the set of pattern discs on said mandrel, and means for controlling both of said operating means; the said machine being characterized in that the mandrel is operated from a first control means comprising a gear box arrangement including gear and camming mechanism, for imparting intermittent relative longitudinal movement between the mandrel and the teeth breaking-off tools; a second control means is provided for, inter alia, controlling the selection of the said breaking-off tools, the aforesaid two control means being caused, at the dictates of a third control means to function strictly in unison with one another, and the machine also including means for relatively adjusting the mandrel and the breaking-off tools to permit the machine to accommodate sets of discs of respectively different diameters.

15. A toothed disc preparation machine according to claim 14, wherein the said means for adjusting the relationship of the mandrel relative to the position of the breaking-off tools consists of a mandrel locating wheel having a plurality of recesses which are laterally offset to respectively different extents from lines extending radially to the axis of the said wheel, the latter being turnable to present a selected one of the recesses, dependent on the diameter of the discs to ,be programmed, for reception of an appropriate part of the mandrel assembly.

16. A toothed disc preparation machine according to claim 14, wherein the said means for adjusting the relationship of the mandrel relative to the position of the breaking-off tools comprise a carriage for locating the mandrel, and cam means for moving this carriage to one of a multiplicity of locations relatively to the breaking-off tools depending on the diameter of the discs to be programmed.

17. A disc preparation machine according to claim 14, wherein there is a fixed mandrel location, and means are provided for moving the teeth breaking tools to different extents in relation to such location depending on the diameter of discs to be programmed.

18. A toothed disc preparation machine according to claim 14, wherein the said third control means consist of electrical switches arranged to control the starting and stopping of a control tape once the programming of a set of discs has been started, said switches being adapted to be triggered from at least one rotary switching device rotating in timed relationship with the gear box arrangement.

19. A toothed disc preparation machine according to claim 18, wherein the electrical switches are contactless vane switches each comprising an oscillator coil and a detector winding, insertion of a metallic vane in a gap between which stops the electrical output.

20. A toothed disc preparation machine according to claim 18, wherein the tape serves to program selective operation of a bank of solenoids of which there is one to each tooth breaking-off tool, the condition of the solenoids at any one time determining whether the corresponding tools are selected to their operative or inoperative positions. 

1. A machine for breaking off the peripheral teeth of pattern discs used on circular jacquard knitting machines comprising, in combination, a mandrel on which are held fast, in axially spaced apart relationship, pattern discs of a set to be operated on at any one time; a corresponding set of teeth breaking-off tools which are selectively operable for action upon the teeth of predetermined ones of the said set of pattern discs; means for automatically operating the mandrel; means for automatically operating the breaking-off tools for the duration of the complete preparation of the set of pattern discs on said mandrel, and means for controlling both of said operating means: the said machine being characterized in that the mandrel is operated from a first control means comprising both a gear box arrangement including gear and camming mechanism for imparting intermittent relative longitudinal movement between the mandrel and the teeth breaking-off tools and also an electrically controlled incremental drive means for intermittently rotating the mandrel from one tooth position to the next, and in that a second control means is provided for, inter alia, controlling the selection of the said breaking-off tools, the aforesaid two control means being caused, at the dictates of a third control means to function strictly in unison with one another.
 2. A toothed disc preparation machine according to claim 1, which also includes means for relatively adjusting the mandrel and the breaking-off tools to permit the machine to accommodate sets of discs of respectively different diameters.
 3. A toothed disc preparation machine according to claim 2, wherein the said last mentioned means consist of a mandrel-locating wheel having therein a plurality of recesses which are laterally offset to respectively different extents from lines extending radially to the axis of the said wheel, the latter being turnable to present a selected one of the recesses, dependent on the diameter of the discs to be programmed, for reception of an appropriate part of the mandrel assembly.
 4. A toothed disc preparation machine according to claim 2, wherein the said last mentioned means comprise a carriage for locating the mandrel, and cam means for moving this carriage to one of a multiplicity of locations relatively to the breaking-off tools depending on the diameter of the discs to be programmed.
 5. A toothed disc preparation machine according to claim 1, wherein there is a fixed mandrel location, and means are provided for moving the teeth breaking-off tools to different extents in relation to such location depending on the diameter of the discs to be programmed.
 6. A toothed disc preparation machiNe according to claim 1, wherein the breaking-off tools are located on a sliding bed and cam means are provided for shogging the said bed and hence also the tools relatively to the mandrel for breaking-off disc teeth.
 7. A toothed disc preparation machine according to claim 5, wherein the means for projecting the said tools into their teeth breaking positions include a group of differently sized cams which is adapted to be shifted to bring the individual cams into operation selectively, one at a time, to effect projection of the tools to respectively different extents radially with respect to the fixed mandrel depending on the diameter of the discs to be programmed.
 8. A toothed disc preparation machine according to claim 1, wherein the said second control means consists of a tape which not only bears the information for controlling the selection of the breaking-off tools but also the information for controlling the starting and stopping of the gear box arrangement, and the indexing information for instructing the electrically controlled incremental drive means by which the mandrel is intermittently rotated.
 9. A toothed disc preparation machine according to claim 1, wherein the electrically controlled incremental drive means for intermittently rotating the mandrel includes a stepper motor.
 10. A toothed disc preparation machine according to claim 8, wherein the said third control means consist of electrical switches arranged to control the starting and stopping of the control tape once the programming of a set of discs has been started, said switches being adapted to be triggered from at least one rotary switching device rotating in timed relationship with the gear box arrangement.
 11. A toothed disc preparation machine according to claim 10, wherein the electrical switches are contactless vane switches each comprising an oscillator coil and a detector winding, insertion of a metallic vane in a gap between which stops the electrical output.
 12. A toothed disc preparation machine according to claim 8, wherein the tape serves, inter alia, to programme selective operation of a bank of solenoids of which there is one to each tooth breaking-off tool, the condition of the solenoids at any one time determining whether the corresponding tools are selected to their operative or inoperative positions.
 13. A toothed disc preparation machine according to claim 8, wherein there is provided an electronic function unit incorporating both a pulse multiplier and a pulse divider wherein electrical pulses controlling the electrically controlled incremental drive means are a predetermined fraction of pulses emitted from a pulse generator at the instruction of the tape.
 14. A machine for breaking off the peripheral teeth of pattern discs used on circular jacquard knitting machines comprising, in combination, a mandrel on which are held fast, in axially spaced apart relationship, pattern discs of a set to be operated on at any one time; a corresponding set of teeth breaking-of tools which are selectively operable for action upon the teeth of predetermined ones of the said set of pattern discs; means for automatically operating the mandrel; means for automatically operating the breaking-off tools for the duration of the complete preparation of the set of pattern discs on said mandrel, and means for controlling both of said operating means; the said machine being characterized in that the mandrel is operated from a first control means comprising a gear box arrangement including gear and camming mechanism, for imparting intermittent relative longitudinal movement between the mandrel and the teeth breaking-off tools; a second control means is provided for, inter alia, controlling the selection of the said breaking-off tools, the aforesaid two control means being caused, at the dictates of a third control means to function strictly in unison with one another, and the machine also including means for relatively adjusting the mandrel and the breaking-off tools to permit the machIne to accommodate sets of discs of respectively different diameters.
 15. A toothed disc preparation machine according to claim 14, wherein the said means for adjusting the relationship of the mandrel relative to the position of the breaking-off tools consists of a mandrel locating wheel having a plurality of recesses which are laterally offset to respectively different extents from lines extending radially to the axis of the said wheel, the latter being turnable to present a selected one of the recesses, dependent on the diameter of the discs to be programmed, for reception of an appropriate part of the mandrel assembly.
 16. A toothed disc preparation machine according to claim 14, wherein the said means for adjusting the relationship of the mandrel relative to the position of the breaking-off tools comprise a carriage for locating the mandrel, and cam means for moving this carriage to one of a multiplicity of locations relatively to the breaking-off tools depending on the diameter of the discs to be programmed.
 17. A disc preparation machine according to claim 14, wherein there is a fixed mandrel location, and means are provided for moving the teeth breaking tools to different extents in relation to such location depending on the diameter of discs to be programmed.
 18. A toothed disc preparation machine according to claim 14, wherein the said third control means consist of electrical switches arranged to control the starting and stopping of a control tape once the programming of a set of discs has been started, said switches being adapted to be triggered from at least one rotary switching device rotating in timed relationship with the gear box arrangement.
 19. A toothed disc preparation machine according to claim 18, wherein the electrical switches are contactless vane switches each comprising an oscillator coil and a detector winding, insertion of a metallic vane in a gap between which stops the electrical output.
 20. A toothed disc preparation machine according to claim 18, wherein the tape serves to program selective operation of a bank of solenoids of which there is one to each tooth breaking-off tool, the condition of the solenoids at any one time determining whether the corresponding tools are selected to their operative or inoperative positions. 